Shotgunnova's guide, which I'm hoping you looked at since it's the only starred walkthrough specifically describes the way the blocks translate to the numbers:
There's a computer room here that demands an 'input code'. It will display something like this diagram, two rows with blocks filling them. '0' is a block unlit, '1' is a block lit.
Which honestly isn't that difficult to figure out yourself.
The actual process of inputting the code is a bit more difficult. When inputting you get to set the bottom row of blocks to on/off however you like, and then by some method based on your input the upper row will change. You need to get the upper row to be the correct pass code.
I'm not 100% positive on the way it works, but I think it may be a process of binary math. from right to left the columns are "added" to produce a new top row. A simple explanation is to again look at the lit up blocks as 1's and the blanks as 0's and add from the left to right making sure to carry a 1 to the next column when appropriate: 0+0+no carry = 0 and no carry 0+1+no carry = 1 and no carry 1+1+no carry = 0 and a carry 0+0+a carry = 1 and no carry 0+1+a carry = 0 and a carry 1+1+a carry = 1 and a carry
[/rant] When Bill Gates invented the Internet he created Ctrl+F for a reason.